package com.icss.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.util.Random;

/**
 * 
 * TODO 产生随机的验证码和验证码图片的类,注意此类只能在实例化是产生验证码，所以一个对象只能一次性使用
 * @author aimicheng
 */
public class VerifyCodeImageGenarator {
	private String content = "";
	private BufferedImage image;
    private static final char [] VERIFY_CODE_CHARS = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
                                  'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'
                                 ,'0','1','2','3','4','5','6','7','8','9'};

    
    public VerifyCodeImageGenarator(){
    	image = createImage();
    }
    
    
    /**
     * TODO 获得验证码内容的方法
     * @return 验证码内容的字符串
     */
    public String getContent(){
        return content;
    }
    
    /**
     * TODO 获得验证码图片的方法
     * @return
     */
    public BufferedImage getImage(){
    	return image;
    }
    
    /**
     * 产生验证码图片的方法
     * TODO
     * @return
     */
    private BufferedImage createImage() {
        // 在内存中创建图象
        int width = 60, height = 20;
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        // 获取图形上下文
        Graphics g = image.getGraphics();
        //生成随机类
        Random random = new Random();
        // 设定背景色
        g.setColor(getRandColor(200, 250));

        //以以上设置画出一个矩形
        g.fillRect(0, 0, width, height);

        //设定字体
        g.setFont(new Font("Times New Roman", Font.PLAIN, 18));

        // 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
        g.setColor(getRandColor(160, 200));
        for (int i = 0; i < 155; i++) {
            int x = random.nextInt(width);
            int y = random.nextInt(height);
            int xl = random.nextInt(12);
            int yl = random.nextInt(12);
            g.drawLine(x, y, x + xl, y + yl);
        }

        // 取随机产生的认证码(4位数字)
        String sRand = "";
        
        int randInt = 0;
        char c;
        content = "";
        for (int i = 0; i < 4; i++) {

            randInt = random.nextInt(62);    //得到一个0至81的数
           
            c = VERIFY_CODE_CHARS[randInt];
            
            sRand = Character.toString(c);
            content += sRand;

            // 将认证码显示到图象中
            g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
            //调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
            g.drawString(sRand, 13 * i + 6, 16);
        }
        return image;
    }

    private Color getRandColor(int fc, int bc) {
        //给定范围获得随机颜色
        Random random = new Random();
        if (fc > 255) {
            fc = 255;
        }
        if (bc > 255) {
            bc = 255;
        }
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }
}
